I have a Frigidaire Elements microwave oven which had the magnatron replaced in february of 2010 (purchased in february of 2008. Magnatron was replaced because the power button and the delay button wouldn't push. Presently, it does not heat. Everything else works, including the convection oven which I just preheated. It is warm. The turntable moves, the fan comes on, the light comes on. Does anyone have any idea of what is wrong here? Thank you. june